Good thread... I used to hunt with a 7RM for many years and 2 years ago when my 7RM throat burned out I ended up going with a 300 WSM. For an all around hunting cartridge, I think the 300 WSM is a little better.
To try to compare apples to apples, if we look at the 7mm (.284 for those who don't like metrics
) 160 AB vs the .308 ( 7.62mm for those who who do like metrics
) 180 AB we will see that typical velocity of bout 3000 fps is common to both. The 7mm 160 has a very slight edge in BC. The 180 bullet has 12.5% more mass and 18% greater unexpanded frontal area, both of which IMO are significant in the effect they transfer to the game animal. Not huge, but significant. Bottom line, trajectory is almost identical with like bullets.
If we move away from apples to apples, RL17 adds a new dimension to short the short mag cartridges. This powder gives me 200 fps more velocity with a 180 gr bullet out of my 300 WSM. I think RL17 will benefit the 7mm as well, but probably not as much as the 300 WSM. I plan to find out relatively soon.
Last, bullet selection... Many say that the 7mm has better bullet selection, and that is somewhat true IF you prefer highly frangible bullets like the 168 and 180 Bergers and 162 Amax's. IMO, the GS HV 30 cal 177 gr bullet, with its BC and velocities, is probably the best LR hunting bullet available in 30 cal or less cartridges, period. Put that together with RL17 in a 300 WSM package and it will easily out distance and out punch a 7 RM with any available powder or bullet.